Bristle sub-assemblies and method of making same

ABSTRACT

A bristle sub-assembly includes first and second base strings and a plurality of polymeric monofilaments connected to and extending between the first and second base strings. The polymeric monofilaments form a first arched row when the first and second base strings are brought together. Several types and configurations of brushes are made using either arched bristles or combinations of arched and straight bristles.

RELATED APPLICATIONS

This is a continuation-in-part of U.S. Ser. No. 09/092,092, filed Jun.5, 1998, now U.S. Pat. No. 6,096,151.

BACKGROUND OF THE INVENTION

The present invention relates generally to articles made of polymericmonofilaments, and more particularly, to looped bristles, methods formaking looped bristles and bristle sub-assemblies, and monofilamentbristle sub-assemblies connected to brush bodies.

The aforementioned co-pending application describes a manufacturingtechnique in which a base string is fed axially along a mandrel while atthe same time a monofilament is wrapped around the mandrel, therebyproducing a plurality of “wraps” which are transported along the mandrelby the base string. The wraps are then bonded to the base string usingan ultrasonic welder, and subsequently cut to thereby form an articlehaving two rows of monofilament segments connected to the base string.

This article, called a “bristle string,” can then be cut to lengths andused to make a variety of brushes or other products requiring bristles.In one example, several rows of bristles are formed in a toothbrush bymounting the bristle string segments in the head portion of atoothbrush. Typically, the proximal ends of the bristles are connectedto the brush head and the distal ends extend freely upwardly.

Brushes with looped bristles have been used in the past. For example,U.S. Pat. No. 4,211,217 to Gueret describes a hair and massage brush inwhich the bristles are bent to form loops which are anchored inperforations formed in the brush head fusing the ends together. Asanother example, U.S. Pat. No. 4,406,032 to Diamant describes atoothbrush which includes a filament wrapped around the head to form aplurality of circular loops.

U.S. Pat. No. 4,493,125 to Collis describes a toothbrush having acombination of curved bristles and straight bristles. The curvedbristles were formed by having opposite ends of straight filamentsembedded in the head of the toothbrush in groups, thereby forming loops.The loops are then cut axially to form two rows of curved bristles.Other examples where looped bristles are used in a toothbrush are shownin U.S. Pat. Nos. 4,030,845 to Deckert, 2,599,191 to Meunier, and4,438,541 to Jacob et al.

While these show various forms of loop bristles, a need exists for alooped bristle structure that is relatively easy to manufacture and costeffective to produce.

SUMMARY OF THE INVENTION

An object of the present invention is to provide means to expand brushdesign beyond the range possible with current tufting techniques.

Another object of the present invention is to provide a bristlesub-assembly for a brush in which individual filaments are positionallyfixed with respect to each other prior to connection to a brush body.

Still another object of the present invention is to provide a method ofassembling brushes in which bristle sub-assemblies can be permanentlyconnected to the brush body or, alternatively, detachably connected forsubsequent replacement, thereby avoiding wastefully discarding otherwisefunctional brush bodies.

Yet another object of the invention is to provide a brush that has acombination of arched bristles, looped bristles and straight bristles,whereby both types of bristles can be assembled without usingconventional tufting techniques.

These and other objects are met by providing a bristle sub-assemblywhich includes two substantially parallel base strings and a pluralityof polymeric monofilaments connected transversely between the two basestrings. When the two base strings are juxtaposed to each other, theyform a single row of arched monofilaments. The row of archedmonofilaments can be sized to a desired length by cutting the two basestrings and then connecting them to a brush head in desired patterns.

Other objects and features of the invention will become more apparentfrom the following detailed description when taken in conjunction withthe illustrative embodiments in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a horizontal sectional view of an apparatus for making bristlesub-assemblies according to a preferred embodiment of the presentinvention, taken at an ultrasonic welding stage;

FIG. 2 is a horizontal sectional view of an apparatus for making bristlesub-assemblies according to a preferred embodiment of the presentinvention, taken at a cutting stage;

FIG. 3 is a plan view of a bristle sub-assembly made with the apparatusof FIG. 1, prior to bending the monofilament segments into archedformations;

FIG. 4 is an end view of a row of arched monofilaments made from thebristle sub-assembly of FIG. 3;

FIG. 5 is a horizontal sectional view of an apparatus for making bristlesub-assemblies according to another preferred embodiment of the presentinvention, taken at a cutting stage;

FIG. 6 is an end view of a bristle string sub-assembly made by theapparatus of FIG. 5:

FIG. 7 is an end view of the bristle string sub-assembly of FIG. 6, bentto form an arch section;

FIG. 8 is a plan view of a bristle sub-assembly made according toanother embodiment of the present invention;

FIG. 9 is an end view of the bristle sub-assembly according to claim 8,after forming a pair of arched segments;

FIG. 10 is a perspective view of a toothbrush made with the archedbristles made according to the present invention;

FIG. 11 is a partial, longitudinal cross-sectional view of the forwardportion of the toothbrush of FIG. 10;

FIG. 12 is an end view of a brush head according to another embodimentof the present invention, and having a row of arched bristles and twoflanking rows of straight bristles;

FIG. 13 is an end view of a brush head according to another embodimentof the present invention, and having a first row of arched bristlesconcentrically disposed with a second row of arched bristles; and

FIG. 14 is an end view of a brush head according to another embodimentof the present invention, and having a row of arched bristles extendingover three longitudinal rows of straight bristles.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1 and 2, a hollow, substantially rectangular mandrel10 has four beveled comers 12, 14, 16, and 18 which include flatsurfaces that are at 45° angles to the contiguous flat surfaces of themandrel 10. Base strings 20, 22, 26, 28, 30, 32, 34 and 36, entering oneaxial end of the mandrel 10, pass downwardly through the interior of themandrel 10. The base strings are turned at the opposite end and guidedfor movement in the opposite direction in pairs along respective comersof the mandrel 10 as shown.

A monofilament 38 is wrapped around the mandrel 10 as the base stringstranslate to thereby form a plurality of wraps that are in contact withthe base strings. The base strings move the wraps under ultrasonicbonding horns 40, 42, 44 and 46, each of which is juxtaposed arespective comer of the mandrel 10. The horns are energized to thermallyfuse the wraps of monofilament to the base strings.

After bonding, the base strings further transport the monofilamentwraps, now connected to the base strings, to a cutting station. As seenin FIG. 2, the cutting station includes a cutting blade 48, 50, 52, and54 disposed at respective comers to cut the monofilament wraps betweeneach pair of base strings to form four separate bristle sub-assemblies.While each cutting blade is shown to be rotatable about an axisillustrated in broken lines in FIG. 2, any suitable mechanical or waveenergy cutting device can be employed.

Referring to FIG. 3, one of the bristle sub-assemblies 56 is shown withtwo base strings 22 and 26, disposed parallel to each other, and theplurality of wraps bonded to the base strings at substantially rightangles to form a plurality of monofilament segments 58. As seen in FIG.4, as the parallel base strings 22 and 26 are moved towards each other,the monofilament segments 58 bend to form an arched row 60 ofmonofilaments.

Other monofilament bristle sub-assemblies can be made by varying thenumber of base strings and re-positioning the slitters. For example, inFIG. 5 the mandrel 62 has a substantially square cross-sectional shape,with base strings 64, 66, 68 and 70 disposed respectively at each of thefour corners of the mandrel 62. A monofilament 72 is wrapped around themandrel 62 and transported by the base strings as before to form aplurality of wraps. After passing under ultrasonic bonders (not shown)and thermally fused to the base strings, the monofilament wraps aretransported to a cutting station which includes two cutting blades 74and 76.

The cutting blades cut the monofilament wraps on opposite sides of themandrel 62 to form two nearly identical bristle string sub-assemblies78, of which one is shown in FIG. 6. The sub-assembly 78 includes aplurality of monofilament segments 80 connecting to and extendingbetween the two base strings 68 and 70, and two rows of monofilamentsegments 82 and 84. As seen in FIG. 7, when the base strings 68 and 70are brought together in the direction of the directional arrows, themonofilament segments 80 form an arch.

In another embodiment, seen in FIG. 8, the monofilament wraps are cut toform a bristle string sub-assembly 86 in which the monofilament segments88 are connected to base strings 90, 92 and 94. As seen in FIG. 9, whenthe two outer base strings 90 and 94 are moved towards the middle basestring 92, as illustrated by the directional arrows, a pair of archedsegments 96 and 98 are formed.

The various bristle sub-assemblies described above can be used in avariety of products, including brushes. FIG. 10 shows a toothbrush 100having a handle portion 102, a head portion 104, and a bristle portionwhich includes straight rows 106, 108, 110, 112, 114 and 116 ofmonofilament bristles, which are alternatingly disposed between archedrows 118, 120, 122, 124 and 126 of monofilament bristles. The straightbristles can be made according to the techniques described in co-pendingapplication Serial No. 09/092,092 entitled Method and Apparatus ForMaking Articles Having Bristles, now U.S. Pat. No. 6,096,151, which isincorporated herein by reference. Alternatively, the straight bristlescan be made by using the techniques described herein with respect to theembodiment of FIG. 7, whereby the straight bristles are made from thestraight segments 82 and 84.

The straight bristles and arched bristle sub-assemblies are assembledwith the head portion 104 by using the techniques described inco-pending application Ser. No. 09/092,094, pending, entitledMonofilament Bristle Assemblies and Methods of Making Brushes UsingSame, which is incorporated herein by reference. For example, and asseen in FIG. 11, the head portion 104 is provided with transversegrooves which receive the single base strings of straight rows 106 and108 and the two base strings of arched rows 118 and 120. Alternatively,straight rows 106 and 108 can share respective grooves with thecorresponding base strings of arched row 118 to form a more compactbrush head. Upon placing the base strings in the grooves, chemical,thermal or mechanical means are used to seal the grooves and lock thebase strings in place.

The bristle sub-assemblies described herein can be used to constructbrushes with a variety of bristle patterns and combinations. FIG. 12,which is a front end view of a toothbrush 128, has two rows 130 and 132of straight monofilament bristles which flank a single row 134 of archedmonofilament bristles. The rows 130 and 132 extend to a height greaterthan the apex of the row 134 of arched monofilaments. All three rowsextend longitudinally from the upper surface of a head portion 136 ofthe toothbrush 128. Each of rows 130 and 132 have a base string mountedin the head portion 136, while row 134 has two base strings mounted inthe head portion, one corresponding to each leg of the archedmonofilaments.

FIG. 13, also a front end view of a toothbrush 138, has two rows 140 and142 of arched monofilament bristles which are disposed concentricallywith respect to each other. Row 140 has an apex greater than that of row142, and the legs of row 140 are disposed outside the legs of row 142.Both rows extend longitudinally from the upper surface of a head portion144 of the toothbrush 138. Each of rows 140 and 142 have two basestrings mounted in the head portion 144.

FIG. 14, also a front end view of a toothbrush 146, has a row 148 ofarched monofilament bristles which run longitudinally along the brushhead 150, and three rows 152, 154, and 156 of straight bristles whichlikewise run longitudinally along the brush head.

The various embodiments described herein can employ virtually anycombination of arched and straight bristle sub-assemblies, and mayfurther include the looped bristle sub-assemblies described in U.S. Ser.No. 09/092,092, now U.S. Pat. No. 6,096,151.

An advantage to the present invention is that the bristle sub-assembliescan be mixed and matched to create a variety of desired arched andstraight bristle combinations. For toothbrush applications, the archedbristles have the additional advantage that there are no distal ends tobe treated, as is the case for straight bristles.

The monofilaments used for both the straight and arched bristlesub-assemblies are each a single filament, as opposed to a“multi-filament,” such as yam, twine, etc., although the monofilamentmay be a co-extrusion of one or more polymers to form a coaxialstructure. The monofilaments may be made of several different materials,including aliphatic polyamides, aromatic polyamides, polyesters,polyolefins, polystyrene, polyvinylchloride (PVC), polyurethane,polyvinylidene chloride, fluoropolymers, styrenes and styrenecopolymers. A particularly suitable polymeric material for toothbrushapplications is 6,12 nylon; other nylons may be used, including 4 nylon,6 nylon, 11 nylon, 12 nylon, 6,6 nylon, 6,10 nylon, 6,14 nylon, 10,10nylon and 12,12 nylon and other nylon co-polymers. An example of apreferred polyester is polybutylene terephthalate (PBT).

When the monofilaments are abutting as in FIG. 3, the interconnection ofadjacent monofilaments to each other in a flow zone may be relativelystrong compared to the interconnection of the base strings to the flowzone which is substantially composed of monofilament material. Thisfeature allows, in some applications, the removal of the base stringsfrom the monofilaments anytime after thermal fusing. Alternatively, theadhesion between the monofilaments and the base string can be at leastas strong as the adhesion between monofilaments.

While FIG. 3 shows the monofilaments in a single row,shoulder-to-shoulder, the density can be varied such that the adjacentmonofilaments do not touch each other. Also, the density may be suchthat a second or greater number of rows of monofilaments are stackedupon each other. Where eight (8) mil nylon monofilament is used, forexample, a density of about 125 monofilaments per inch of base stringcan be achieved with a single row, shoulder-to-shoulder monofilaments.

While toothbrush embodiments have been described, any of the widevariety of known brushes could be constructed using the arched bristles,arch-and-loop bristle combinations or arch-and-straight bristlecombinations according to the present invention. For some brushapplications, the monofilaments may include abrasive particles or gritmaterial for particular brush applications. Abrasive monofilaments arecommercially available under the name TYNEX® A by E.I. Du Pont DeNemours and Company of Wilmington, Del. USA. Preferably, the abrasivematerial comprises 0-50% by weight of the polymeric monofilaments.TYNEX® A is a 6,12 nylon monofilament containing particles of siliconcarbide or aluminum oxide, which are distributed throughout themonofilament.

When ultrasonic welding is used, at least the monofilament or the basestring, preferably both, are made of thermoplastic polymeric materials.These have been described above in reference to other embodiments.

The monofilaments used in any of the above embodiments may beco-extrusions of one or more polymers. Also, to achieve the desiredphysical characteristics of the bristles used for applications such ascleaning and scrubbing brushes, it has been found that the preferredmonofilaments are those having a diameter between 2 and 200 mils, andpreferably between 2 and 20 mils. In a particularly preferred embodimentfor the toothbrush, the monofilaments are 4-10 mils in diameter.Monofilaments of different diameters, cross-sections, materials, surfaceproperties and/or colors can be combined in one bristle assembly orsub-assembly to achieve specific brushing characteristics and/orappearance.

In embodiments using nylon for either the monofilament or the basestring, or both, a preferred nylon is sold under the name TYNEX®, and ismanufactured by E.I. Du Pont De Nemours and Company of Wilmington, Del.USA. TYNEX® is polyhexamethylene dodecanamide, which is the technicalname for 6,12 nylon. It has a melting point of between 208 and 215° C.and has a specific gravity of 1.05-1.07, and is available commerciallyin many shapes and diameters.

Monofilaments and/or base strings suitable for use in the presentinvention can have shapes other than circular cross-sections, and may behollow or have voids in their cross-section. Embodiments described aboveshow circular cross-sectional shapes for the base string andmonofilaments. Either or both the base string and monofilaments couldhave oval, rectangular, or other shapes. In any shape, the preferredthicknesses for the base string and monofilaments are selected toprovide a level of functionality to the individual brush applications.

With respect to the base string, the preferred embodiments describedabove show a single strand of monofilament material. However, the basestring could be a bundle of monofilaments having at least one of themonofilaments made of polymeric thermoplastic material.

The polymeric monofilaments used for bristles in the various embodimentsdescribed above can have other additives. For example, the polymericmonofilaments could include 0-50% by weight particles having finctionaland/or aesthetic quality. One example would be particulate material thatprovides a color feature that would enhance the visual appearance of thebristles. Other functional particles could also be included such asanti-microbial additives in the polymeric monofilaments. Otherparticulate materials or coatings may be applied to or embodied withinthe monofilament such as therapeutic agents or colorants, or otherdesirable additives. Also, the monofilaments may be surface treated toprovide desired properties, such as to alter frictional coefficient.

The embodiments described above require “connection” between themonofilaments and the base string. In this context, “connection” meansthat the monofilaments are attached to the base string by a frangiblejoint formed by melting, adhesive bonding, solvent bonding, or similarmeans. The degree of frangibility can be controlled so that, if desired,the base string can be easily separated from the monofilaments afterbonding.

The arched bristles described herein can be put on any brush head in anyconfiguration or pattern. For example, the arched bristles may runparallel to or transverse the longitudinal axis of the brush head, ortransverse and longitudinal bristles can be used concurrently. The headitself can have a substantially flat surface from which the bristlesextend upwardly, as shown in the illustrated embodiments. Alternatively,the brush head can have a shaped, i.e., curved surface, in which casethe bristles would tend to fan outwardly, for the case of a convexsurface, or fan inwardly for the case of a concave surface. Also, thetwo base strings of an arched bristle sub-assembly can be mounted in thebrush head in a non-parallel fashion, such that the arched row ofbristles adopt a desired profile in which the apex of the arch changesalong the length of the row.

Although the invention has been described with reference to severalparticular embodiments, it will be understood to those skilled in theart that the invention is capable of a variety of alternativeembodiments within the spirit and scope of the appended claims.

What is claimed is:
 1. A bristle sub-assembly comprising: (a) first andsecond base strings, (b) a plurality of monofilaments extending betweenthe first and second base strings, and (c) a flow zone forming frangiblejoints connecting the monofilaments to the first and second basestrings, whereby the monofilaments form a first arched row between thefirst and second base strings.
 2. A bristle sub-assembly according toclaim 1, wherein at least one of the base strings and the monofilamentsare made of a polymeric material.
 3. A bristle sub-assembly according toclaim 2, wherein the polymeric material is a thermoplastic polymericmaterial.
 4. A bristle sub-assembly according to claim 1, wherein atleast one of the base strings and the monofilaments are made of amaterial selected from the group consisting of aliphatic polyamides,aromatic polyamides, polyesters, polyolefins, styrenes,polyvinylchloride (PVC), fluoropolymers, polyurethane, polyvinylidenechloride, polystyrene and styrene copolymers, and co-extrusions of atleast one polymer.
 5. A bristle sub-assembly according to claim 1,wherein at least one of the base strings and the monofilaments are madeof a nylon material.
 6. A bristle sub-assembly according to claim 5,wherein the nylon material is selected from the group consisting of 4nylon, 6 nylon, 11 nylon, 12 nylon, 6,6 nylon, 6,10 nylon, 6,12 nylon,6,14 nylon, 10,10 nylon and 12,12 nylon and other nylon copolymers.
 7. Abristle sub-assembly according to claim 1, wherein at least one of thebase strings and the monofilaments are made of polybutyleneterephthalate (PBT).
 8. A bristle sub-assembly according to claim 1,wherein at least one of the base strings is a monofilament made ofthermoplastic material having a diameter of 2-200 mils.
 9. A bristlesub-assembly according to claim 1, wherein the base string is a bundleof monofilaments, at least one of which is made of a thermoplasticpolymeric material.
 10. A bristle sub-assembly according to claim 1,wherein the monofilaments are heat fused to the base strings.
 11. Abristle sub-assembly according to claim 1, wherein the monofilaments aresolvent bonded to the base strings.
 12. A bristle sub-assembly accordingto claim 1, wherein the monofilaments have a diameter between 2 and 200mils.
 13. A bristle sub-assembly according to claim 1, wherein themonofilaments have varying diameters between 2 and 200 mils.
 14. Abristle sub-assembly according to claim 1, wherein at least one of thebase strings and the monofilaments have substantially circularcross-sectional shape.
 15. A bristle sub-assembly according to claim 1,wherein at least one of the base strings and the monofilaments havesubstantially non-circular cross-sectional shape.
 16. A bristlesub-assembly according to claim 1, further comprising a third basestring disposed between the first and second base strings and connectedto the monofilaments, whereby the monofilaments form the first archedrow between the first and third base strings, and form a second archedrow between the second and third base strings.
 17. A bristlesub-assembly according to claim 1, wherein at least one of the basestrings is a monofilament made of thermoplastic material having adiameter of 2-200 mils.
 18. A bristle sub-assembly according to claim 1,wherein the base string is a bundle of monofilaments at least one ofwhich is made of a thermoplastic polymeric material.
 19. A brushassembly comprising: (a) a brush body having a head; and (b) a firstbristle sub-assembly connected to the head of the brush body, whereinthe first bristle sub-assembly comprises (i) first and second basestrings, (ii) a plurality of monofilaments extending between the firstand second base strings, and (iii) a flow zone forming frangible jointsconnecting the monofilaments to the first and second base strings; andwherein the monofilaments form a first arched row that extends upwardlyfrom the brush body.
 20. A brush assembly according to claim 19, whereinat least one of the base strings and the monofilaments are made ofpolymeric material.
 21. A brush assembly according to claim 19, whereinat least one of the base strings and the monofilaments are made ofthermoplastic material.
 22. A brush assembly according to claim 19,wherein the first and second base strings are each at least a singlemonofilament made of a polymeric thermoplastic material.
 23. A brushassembly according to claim 19, wherein at least one of the base stringsand the monofilaments are made of a material selected from the groupconsisting of aliphatic polyamides, aromatic polyamides, polyester,polyolefins, styrenes, polyvinylchloride (PVC), fluoropolymers,polyurethane, polyvinylidene chloride, polystyrene, and styrenecopolymers and co-extrusions of at least one polymer.
 24. A brushassembly according to claim 19, wherein at least one of the base stringsand the monofilaments are made of a nylon material.
 25. A brush assemblyaccording to claim 24, wherein the nylon material is selected from thegroup consisting of 4 nylon, 6 nylon, 11 nylon, 12 nylon, 6,6 nylon,6,10 nylon, 6,12 nylon, 6,14 nylon, 10,10 nylon and 12,12 nylon andother nylon co-polymers.
 26. A brush assembly according to claim 19,wherein at least one of the base strings and the monofilaments are madeof polybutylene teraphthalate (PBT).
 27. A brush assembly according toclaim 19, wherein the monofilaments are heat fused to the first andsecond base strings.
 28. A brush assembly according to claim 19, whereinthe monofilaments are solvent bonded to the first and second basestrings.
 29. A brush assembly according to claim 19, wherein themonofilaments have a diameter between 2 and 200 mils.
 30. A brushassembly according to claim 19, wherein the monofilaments have diametersthat vary between 2 and 200 mils.
 31. A brush assembly according toclaim 19, further comprising at least a second bristle sub-assemblyconnected to the head of the brush body, wherein the second bristlesub-assembly comprises (a) at least third and fourth base strings; and(b) a plurality of polymeric monofilaments that are connected to andextend between the third and fourth base strings, and form a secondarched row that extends upwardly from the brush body.
 32. A brushassembly according to claim 31, wherein the first and second arched rowsare mounted longitudinally and concentrically on the brush body.
 33. Abrush assembly according to claim 31, wherein the first and secondarched rows are mounted transversely on the brush body.
 34. A brushassembly according to claim 18, further comprising at least one row ofstraight monofilament bristles, assembled with the head of the brushbody, each row including a plurality of monofilament bristles extendingupwardly from a base string.
 35. A bristle sub-assembly comprising: (a)first and second base strings, (b) a plurality of monofilamentsextending between the first and second base strings, and (c) adhesiveforming frangible joints connecting the monofilaments to the first andsecond base strings, whereby the monofilaments form a first arched rowbetween the first and second base strings.
 36. A bristle sub-assemblyaccording to claim 35, wherein at least one of the base strings and themonofilaments are made of a polymeric material.
 37. A bristlesub-assembly according to claim 36, wherein the polymeric material is athermoplastic polymeric material.
 38. A bristle sub-assembly accordingto claim 35, wherein at least one of the base strings and themonofilaments are made of a material selected from the group consistingof aliphatic polyamides, aromatic polyamides, polyesters, polyolefins,styrenes, polyvinylchloride (PVC), fluoropolymers, polyurethane,polyvinylidene chloride, polystyrene and styrene copolymers, andco-extrusions of at least one polymer.
 39. A bristle sub-assemblyaccording to claim 35, wherein at least one of the base strings and themonofilaments are made of a nylon material.
 40. A bristle sub-assemblyaccording to claim 39, wherein the nylon material is selected from thegroup consisting of 4 nylon, 6 nylon, 11 nylon, 12 nylon, 6,6 nylon,6,10 nylon, 6,12 nylon, 6,14 nylon, 10,10 nylon and 12,12 nylon andother nylon copolymers.
 41. A bristle sub-assembly according to claim35, wherein at least one of the base strings and the monofilaments aremade of polybutylene terephthalate (PBT).
 42. A bristle sub-assemblyaccording to claim 35, wherein the monofilaments have a diameter between2 and 200 mils.
 43. A bristle sub-assembly according to claim 35,wherein the monofilaments have varying diameters between 2 and 200 mils.44. A bristle sub-assembly according to claim 35, wherein at least oneof the base strings and the monofilaments have substantially circularcross-sectional shape.
 45. A bristle sub-assembly according to claim 35,wherein at least one of the base strings and the monofilaments havesubstantially non-circular cross-sectional shape.
 46. A bristlesub-assembly according to claim 35, further comprising a third basestring disposed between the first and second base strings and connectedto the monofilaments, whereby the monofilaments form the first archedrow between the first and third base strings, and form a second archedrow between the second and third base strings.
 47. A brush assemblycomprising: (a) a brush body having a head; and (b) a first bristlesub-assembly connected to the head of the brush body, wherein the firstbristle sub-assembly comprises (i) first and second base strings, (ii) aplurality of monofilaments extending between the first and second basestrings, and (iii) adhesive forming frangible joints connecting themonofilaments to the first and second base strings; and wherein themonofilaments form a first arched row that extends upwardly from thebrush body.
 48. A brush assembly according to claim 47, wherein at leastone of the base strings and the monofilaments are made of polymericmaterial.
 49. A brush assembly according to claim 47, wherein at leastone of the base strings and the monofilaments are made of thermoplasticmaterial.
 50. A brush assembly according to claim 47, wherein the firstand second base strings are each at least a single monofilament made ofa polymeric thermoplastic material.
 51. A brush assembly according toclaim 47, wherein at least one of the base strings and the monofilamentsare made of a material selected from the group consisting of aliphaticpolyamides, aromatic polyamides, polyester, polyolefins, styrenes,polyvinylchloride (PVC), fluoropolymers, polyurethane, polyvinylidenechloride, polystyrene, and styrene copolymers and co-extrusions of atleast one polymer.
 52. A brush assembly according to claim 47, whereinat least one of the base strings and the monofilaments are made of anylon material.
 53. A brush assembly according to claim 52, wherein thenylon material is selected from the group consisting of 4 nylon, 6nylon, 11 nylon, 12 nylon, 6,6 nylon, 6,10 nylon, 6,12 nylon, 6,14nylon, 10,10 nylon and 12,12 nylon and other nylon copolymers.
 54. Abrush assembly according to claim 47, wherein at least one of the basestrings and the monofilaments are made of polybutylene teraphthalate(PBT).
 55. A brush assembly according to claim 47, wherein themonofilaments have a diameter between 2 and 200 mils.
 56. A brushassembly according to claim 47, wherein the monofilaments have diametersthat vary between 2 and 200 mils.
 57. A brush assembly according toclaim 47, further comprising at least a second bristle sub-assemblyconnected to the head of the brush body, wherein the second bristlesub-assembly comprises (a) at least third and fourth base strings; and(b) a plurality of polymeric monofilaments that are connected to andextend between the third and fourth base strings, and form a secondarched row that extends upwardly from the brush body.
 58. A brushassembly according to claim 57, wherein the first and second arched rowsare mounted longitudinally and concentrically on the brush body.
 59. Abrush assembly according to claim 57, wherein the first and secondarched rows are mounted transversely on the brush body.
 60. A brushassembly according to claim 47, further comprising at least one row ofstraight monofilament bristles, assembled with the head of the brushbody, each row including a plurality of monofilament bristles extendingupwardly from a base string.